| 摘要 |
<p>The electronic anti-theft device for vehicles has an alarm triggered in the event of a break in attempt or theft. A detecting unit is triggered by a fall in battery voltage using a capacitor in parallel with the polarisation resistance of the base of a transistor. A memory circuit holds the resulting signal. This is followed by a first delay, then a power stage controlling a solenoid relay controlling a sounding alarm. Finally a second delay stops the alarm after a preset time. The system may be stopped through an interruptor switch. It is easily fitted into the existing electrical system of a vehicle using e.g. inside light or boot light and the battery. A kaxon or siren is added also in interruptor switch with two additional thin leads which are suitably concealed.</p> |
